These days, numerous types of different building playthings are known. The common feature of all these is that through assembling identical or several types of different building elements various objects can be assembled. One of the most widespread playthings of this kind is the building plaything known as "LEGO". With that, and with playthings of similar kind, particular objects can be assembled out of several kinds of minute building elements which elements are, however, identical by sort.
With this sort of building playthings the point of the playing is the assembling that develops the combinatory skills of children to a major extent. However, the assembled objects are suitable for further playing, with a very few exceptions, only to a limited extent, and further use is not a target upon assembly either.
In addition to the building elements, generally additional accessories have to be used for proper shaping of the various objects, the accessories usually being prefabricated pieces. Through their application, children will learn how to use building elements as modules but it will provide no genuine construction experience because no more has to be performed in each instance than inserting the particular piece prefabricated at the module level.
With other types of building playthings through assembly a structure or object suitable for further utilization is created. Here the aim of the game, in addition to assembling, is shaping a serviceable structure to be suitable for further playing. Such a building plaything is shown in the patent specification and drawings of the U.S. Pat. No. 5,344,143, which is a marble run game comprising building elements used as block elements. Each of the block elements has a top surface and at least one side surface and these surfaces define the groove for travel of a marble. The groove, as shown in the figures, can determine straight, curved, spiral, sloped etc. runs of the marble. In such playthings the main problems are that the run of the marble is either too slow or too fast, further the marble has sometimes an unwanted tottering sideways motion which in fact spoil the play and cause the complete failure of the plaything. The same disadvantage occurs with the plaything shown in the figures of the U.S. Pat. No. 5,344,143. Here, the shape of the cross-section of the groove is a semicircular arch. The marble is supported on one point of the groove and, for this reason, it can have an unrequired to-and-fro sideways motion which results in a drop in speed.